Depending on the application, your bearings better be built to stand the heat. High-temperature environments can cause serious issues for bearings without proper heat stabilization. While a standard bearing can typically handle temperatures up to 300° Fahrenheit, anything higher can lead to a litany of problems that can impact the effectiveness and overall lifespan of your bearings.
One such issue is that extreme heat can cause additional wear and tear on your parts. Thanks to its effects on the microstructure of bearing materials, excess heat can lower the estimated life of a bearing. This is especially problematic because the friction created during bearing rotation creates even more heat, which in turn makes the environmental effects of your application even more prominent for improper bearings. The effects of heat on metal can also cause untreated bearings to expand. This process can warp your parts, which can cause clearances to tighten and eventually force the part to seize up and cease to work.
Bearing seals also require proper stabilization for high-temperature environments. Traditional rubber seals and other improper parts can cause bearing grease to release its oil. This purge can cause the oil to leak into other components in your application or products, which can lead to contamination and other unwanted, costly side effects. The grease itself can also pose a problem. Like standard bearings, a typical grease is effective up to 300 degrees, but will purge all oils in higher temperatures. Once the grease dries up, your bearings will endure more friction and break down faster than expected.
In addition to issues that can cause part deterioration and failure, there are some other ways that high temperatures can impact your bearings. For example, heat-treated bearings make up for the addition of friction-related heat by operating at lower RPMs than standard bearings. This means that you should consider the RPMs of high-temperature bearings if your application runs at higher speeds.
High-temperature environments can also call for softer metals to stabilize the steel during heat treatment. While this process prepares your bearings for extreme heat, lower steel hardness does increase the potential for increased wear at higher speeds. Proper load support is also critical. Higher operating temperatures support lower loads, so it can be valuable to identify and use a material that features a higher natural temperature range.